Office file formats - Computer Definition

Starting with Office 2007, Microsoft switched to Office Open XML (OOXML) as the default file formats for its applications. However, the legacy .doc (Word), .xls (Excel) and .ppt (PowerPoint) file formats are still supported in Office and widely used for compatibility with documents created in versions of Office from Office 97 to Office 2003. The older, legacy formats are used worldwide and are expected to remain popular for years. For more details on the new formats summarized below, see Office Open XML.
OFFICE OPEN XML (OOXML) DEFAULT FILE EXTENSIONS(As of Office 2007)WORD
.docx Document
.docm Macro
.dotx Template
.dotm Template and macro
EXCEL
.xlsx Worksheet
.xlsb Fast binary worksheet
.xlsm Macro
.xltx Template
.xltm Template and macro
.xlam Add-in and macro
POWERPOINT
.pptx Presentation
.pptm Macro
.potx Template
.potm Template and macro
.ppam Add-in
.ppsx Slide show
.ppsm Slide show and macro